The charged particle beam apparatus such as scanning electron microscopes obtains a high-magnification image of a sample by irradiating the sample with a charged particle beam to detect secondary particles such as secondary electrons or reflection electrons and by associating detected signals with the positions irradiated with the charged particle beam.
In recent years, fine samples have often been observed in tilted relation to the charged particle beam. For example, tilted observation is effective when: (1) it is desired to observe a tilted surface of the sample by irradiating that surface perpendicularly with the charged particle beam; (2) it is desired to view the sample three-dimensionally; (3) the characteristics of a crystal are changed when its direction or inclination is varied; (4) different characteristics are obtained depending on the reflection angle of charged particles; or (5) it is desired to minimize absorption of charged particles by the sample and alleviate charge-up for better viewing. As will be appreciated from the above, it has become important to observe fine samples in a state tilted at a precise angle.
Patent Document 1 describes an electron microscope that has an imaging device for obtaining a sample stage image. The sample stage image acquired by the imaging device is used on the display device to display information about the position of the sample on the sample stage where the sample image has been obtained.